When an electronic component having conductive members, such as a wiring, an electrode, and a contact part, can be produced by adopting a production process during which the electronic component is not exposed to an oxidizing atmosphere, pure Cu is used as a wiring or electrode material, as represented by an LSI wiring. On the other hand, in a typical production process for, such as a large-sized plasma display, a metal wiring is embedded in a glass dielectric and subjected to a heat treatment in an oxidizing atmosphere in a high temperature region of, for example, 400° C. or higher, during the production process. In addition, an electrode in a solar cell, low-temperature co-fired ceramics (LTCC), or the like, is produced in a process in which the electrode is fired in the atmosphere at a further higher temperature. Accordingly, an Ag wiring, or the like, having resistance to oxidation even in a high temperature heat treatment (reduced at a high temperature) has been put into practical use for a conductive member handled in a high temperature production process associated with an oxidizing atmosphere. Accordingly, it is strongly desired to use a Cu-based material having high reliability in a wiring in terms of cost reduction and improvement in the migration resistance property. However, Cu causes the troubles that Cu lacks conductivity due to an oxidation occurring at a temperature higher than 200° C., and that bubbles, etc., are remarkably generated in a glass dielectric when Cu is in contact with the glass dielectric, or the like. Accordingly, under the present circumstances, the use of pure Cu metal alone in wiring has not been put into practical use in the electronic component products handled in a high temperature production process associated with an oxidizing atmosphere.
In a conventional technique, an electronic component material has been known in which the weatherability of Cu as a whole is improved by containing Cu as a main component and 0.1 to 3.0% by weight of Mo, and by uniformly mixing Mo into grain boundaries of Cu (e.g., Patent Document 1). In the conventional technique, addition of Mo is essential and an attempt for further improving the weatherability in comparison with the case where only Mo is added, has been made in which a total amount of 0.1 to 3.0% by weight of one or more elements selected from the group consisting of Al, Au, Ag, Ti, Ni, Co, and Si as well as Mo are added. However, it is pointed out that, in the alloy, addition of a total amount of 3.0% by weight or more of one or more elements selected from the group consisting of Al, Au, Ag, Ti, Ni, Co, and Si adversely deteriorates the weatherability. In addition, because the addition of Mo is essential, there has been the problem that the material is high in cost, and accordingly is not suitable for the practical use of electronic component products of low market cost.